Method for making toothed fasteners



Nov. 17, 1936. J. s. MOCHESNEY 2,061,035

METHOD FOR MAKING TOOTHED FASTENERS Filed Sept. 1'7, 1932 2 Sheets-Sheet 1 Nov. 17, 1936. J 5 'MccHEsNEY 2,061,035

METHOD FOR MAKING TOOTHED FASTENERS Filed Sept. 17, 1952 2 Sheets-Sheet 2 lnventor' Wwss: @LW

Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE METHOD FOR MAKING TOOTHED FASTENERS Chesney, individually Application September 17, 1932, Serial No. 633,611

34 Claims.

The invention of this application, wherein I have disclosed certain novel modes of procedure whereby a flat metal strip is subjected to a swa ing process performed without removing metal from the strip, so as to result in a sharpened toothed penetrating end, the opposite faces of the teeth being beveled, and the points of the teeth being subsequently positioned in staggered random relation with respect to the medial plane of the fastener during the corrugating of the presharpened strip, to produce the completed corrugated fastener in accordance with the disclosures of prior application filed by me on Corrugated metal fastener, Application No. 615,512 filed on June 6, 1932, and my application on Machine for making and driving corrugated fasteners, executed of even date.

According to my invention a length of smooth, flat metal strip of the required width, gauge and temper, is first swaged and slit longitudinally between the parallel side edges thereof, to produce a continuously beveled, sharp cutting, work hardened, penetrating end which is of beveled or of V- shaped appearance when viewed in end section, on each of the simultaneously swaged, slit and oppositely beveled strips. In one embodiment of my invention the point of intersection of the planes of the bevel between the longitudinal sides of the strip, form the continuous sharp-cutting, knife-like edge of the penetrating end of the fastener, whereas in another embodiment the cutting edge coincides with one face edge of the ribbon.

Said fiat metal strip in its initial form is first moved in the direction of its length toward the corrugating end of the machine, both edge portions of the strip confined in sliding contact with suitable guides whereby the strip is positioned in pre-determned relation with respect to the toothforming, corrugating, severing and driving mechanism. Said tooth-forming mechanism may be in the form of rotary swaging dies or rolls, as disclosed in said pending applications or by straight line swaging dies, the cutting edges of which lie in parallel, oppositely disposed planes and opposingly impress the tooth form into the metal strip, by up and down straight line motion. The metal strip is slit into strips without the removal of metal in the forming thereof, resulting in beveled, inclined surfaces upon the respective faces of the penetrating edge of said strip. The edges of the swage-beveled teeth and the area bounded by the beveled sides are of V-shaped formation when viewed in end section and are of greater density and greater work-hardness than the metal of the strip adjacent thereto. I prefer, however, to opposingly swage the metal of the strip in successive stages for the purpose of compressing the metal, thereby to avoid excessively upsetting the metal adjacent the swaged portion and also gradually relieving or lessening the side pressure of the swaging rolls or dies on the previously beveledv surfaces by successively decreasing the included angle of the beveling portion of the swaging die or roll. Each stage of the swaging process forms embryonic, oppositely faced, interspaced teeth and continues the swaging process until the completed teeth are produced by severing the ribbon into two strips, thereby forming sharp-cutting penetrating ends on each severed metal strip.

Each of said strips, upon severance from the original fiat strip is adapted to the manufacture of corrugated fasteners and is provided with a sharp cutting penetrating end of toothed formation and a straight relatively blunt driving end and is formed without the removal of metal during the machining thereof. Thereafter the strip continues to advance in the direction of its length into combined pulling, corrugating, and feeding rolls, wherein both of said pre-sharpened strips are corrugated by bending and rebending the same to produce corrugations which extend alternately on each side of the medial line of strips, thus producing a completed corrugated fastener strip. One or both of said strips may be provided with parallel corrugations .or with divergent corrugations as desired by providing corrugating rolls of the desired contour.

At a certain stage in the formation of the corrugations of the sharpened strips by the action of said corrugating mechanism of one form or another as disclosed in my pending applications, the points of the teeth are positioned in unsymmetrical or random staggered relation with respect to the plane of the medial line of the fastener.

Other features and advantages of my invention will appear from the following detailed description taken in connection with the drawings.

In the drawings, Figure 1 is a perspective view of a fiat, swaging die adapted to straight line use, as in a punch press, for the swaging of the beveled, sharp cutting teeth of the penetrating end of the fastener. Fig. 2 is a plan view of the same, illustrative of the toothed arrangement of 50 the cutting edge of the die and the inclined bevel-forming sides thereof. Fig. 3 is a View in elevation and partly in section of opposed rotary swaging dies or rolls adapted to swage and to sever metal strip, shown in forced engagement 5 penetrating end thereby to impart with the metal strip of the fastener in section. Fig. 4 is a plan view of as much of a corrugated fastener making and driving machine as is necessary to the understanding of my invention. Fig. 5 is a plan view of a metal strip illustrative of a progressive method which I employ in the swaging of a metallic ribbon to form two strips Without the removal of metal in the forming of a penetrating end on each of the simultaneously severed strips. Fig. 6 is an enlarged front elevation of a completed toothed fastener i-l'lustra tive of the random staggered position of the tooth points with respect to the medial line of the fastener. Fig. 7 is an enlarged perspectwe View of the same.

In the machine for carrying out my method I employ one strip of metallic ribbon indefinite as to length and of the required gauge, temper and width, to simultaneously produce, when ad vanced in the direction of its length and positioned'. in predetermined gauged relation and guided in. a definite path with respect to combinedswaging and severing dies or rolls, two sharpened strips of fastener stock, each strip having a blunt driving end and a knife-like, sWage-beveled, penetrating end, the swaged por-- tion being V shaped when viewed in end section. The major portions of these operations are carried out upon a table, A The supports of the table, as well as the actuating mechanism, are in partomitted to avoid confusion in the drawings. The table A has an aperture E at the entering. end. of the machine into which the metallic ribbon R; enters thru strip-receiving and positioning guides G acting to align the ribbon with respect to the cutting edge S of the beveled surfaces S of the rotary toothed swaging dies S said rolls act upon the ribbon in opposed forced relation resulting in dividing the ribbon into two strips R and R having a blunt driving end B and a swage-beve'le'd and sw'age-s'harpened penetrating end R The ribbon or strip may be completely swages'evered,- swage-bevel'ed and swage-sharpened upon passing thru the first pair of combined swaging and slitting rolls, or preferably, by a succession of passes thru a series of combined toothed swaging and ribbon slitting rolls, in which case an embryonic swage-beveled toothed is formed successive passes thereafter completing the severance of the rib bon form-ing two sharpened, beveled strips, each strip having a beveled V-shaped penetrating end, when viewed in end section, the metal of the V of greater Work-hardness and of greater density than the surrounding metal of the fastener; thereafter, the strips continue to advance in the direction of their length thru corrugating rolls C of the parallel type or of the divergent type parallel corrugations or divergent corrugations to the toothed strip as desired, said rolls exerting a pulling, cor'rugating and feeding action to the strip which then passes thru corrugated strip guides G across the .path of co-acting fastener severing knives K and K which are adapted to sever the fastener into desired lengths.

The metallic ribbon may be machined by opposed swaging dies S provided with lands S of the straight contacting type, as shown in Fig. 1 and Fig. 2, adapted to punch press operations for producing the severed strip of Fig. 5. It is obvious that in the method of producing the fastener, either by the straight line type of dies each strip- S shown in Fig. 1 and Fig. 2, or the rotary type S shown in Fig. 3, that in the employment of either type, I do not remove metal from the strip in the forming of the finished sharp-cutting swage-beveled, penetrating ends R of the severed strips R and R that the lands S protect the adjacent cutting edges S of both the straight and the rotary type of dies or rolls and function to maintain the opposed cutting edges S out of contact each with the other during the swaging operation by maintaining fixed predetermined spaced relation, thereby preventing damage to the cutting edges.

The machine is power driven and may be continuously operated. or intermittently operated by a step: by step movement through drive shaft F mounted on suitable hearings on the table A A series of spiral drives F fixedly mounted on shaft F transmit motion through connecting gears F (one being shown in Fig. 3) on shafts F to advancethe ribbon R in the direction of its length from the entering end E through a series of positioni-ng guides G then through one or more paired co-acti ng swage-beveling and. ribbon slittingrolls S and then through co-acting flattening rolls U, then through co-acting combined corrugatin-g, pulling, tooth positioningand feeding rolls C said. rolls S and U being interchangeable as to position. The rolls S U and C are keysecured on roller-receiving drive shafts F and F, the former being adjustable and located above the path of the metallic ribbon and the shafts F being. on the lower side thereof, as shown in Fig. 4. The adjusting screws T contact movable halfbearings T and by turning the respective screws the shafts F and the corresponding rollers S can be adjusted with respect to the cooperating rollers S on shaft F to take up play in the bearings and assurethat the opposed cutting edges S may impress their reverse formations into the side surfaces of the ribbon R to the proper depth. Inthe Same manner the rolls are caused to move inweirdly" and outwardly across the path of the strips R and R To avoid damaging the cutting edges S 'of the cooperating rolls S by contact of one edge with the other, I employ lands S having relatively large areas of contact adjacent the swage-b'eveling elements. The lands preferably provide a clearance of from one to two thousandths of an inch between the opposed cutting edges.

The drive shafts F and the opposed fixedly positioned shafts F are timed preferably by'spur gearing F F and operate in registering relation each with the other thus to maintain the opposed cutting edges S of the rotary swaging dies positioned to produce on the metallic ribbon well defined apices P and inclined bevels B and cutting edges R of toothed or scalloped formation.

The rotary type of swaging die S as shown in detail in Fig. 3, and in elevation in Fig. 4 or the straight line type of swaging die shown in Fig. 1 and Fig. 2 are both well adapted to produce toothed formations by imparting their reverse formations in registration to opposite surfaces between the longitudinal side edges thereof, as most clearly illustrated in Fig. 5. During the formation of the penetrating end by the rotary type of die, a slight upset in the metal occurs at the surface edge of the strip adjacent to the bevel's; the height of the upset metal above the longitudinal surface of the strip is dependent upon the physical. characteristics of the metal of the Strip. In order to re-position and to return 2. The method of producing metallic fasteners the upset metal within the surface of the strip, I provide co-acting flattening rolls U mounted on bearings of the type shown in Fig. 3, one of which is adjustable and the other stationary as before described; the action of the rollers upon the surface of the stock returns the upset metal within the surface of the strip.

By employing swaging dies of the straight line type 'as illustrated in Fig. l and Fig. 2, I am enabled to produce the penetrating end of my fastener free from upset metal at the surface edge of the strip adjacent the bevels. I

When two dies are employed of a configuration shown in Fig. 1, the ribbon is severed into two strips, each strip having reversed beveled toothed surfaces intersecting substantially in the line of the medial plane of the strip, forming a cutting edge midway of the longitudinal face of the strip. When one die is employed similar to Fig. 1 in combination with a plain surfaced die the ribbon is severed into two strips, each strip having beveled toothed surfaces and a cutting edge lying on one longitudinal face of each strip, that is, each strip is provided with a single beveled toothed surface.

The swaging dies S opposingly impart their reverse formations in register into the surface of the ribbon R between the longitudinal side edges and the swaged metal travels against the beveled surfaces S to produce work-hardened, burnished, smooth surfaces to the bevels at the penetrating end of the fastener.

The mated corrugated rolls C may be of any desired formation adapted to impart either parallel or divergent corrugations to the strip or they may be moved out of contact with the strips R and R, by retracting the screws T The strip is advanced in the direction of its length through entering end E of the machine through a series of positioning guides G then through rotating, swaging elements S to successively impart to the penetrating end of the strip R a beveled formation R each passage through each succeeding roll S increasing the depth of the bevels and the potential cutting edge until severance occurs, thereby to form two beveled strips R and R each strip having well defined inter-spaced teeth on the sharp penetrating end. Both strips R and R then advance and the strip R passes between the corrugating rolls C and the then corrugated strip continues to advance into the guides G and the severed fastener retaining guides G. A stationary severing knife K co-acts with a movable severing knife K to effect severance of a predetermined length of fastener R"; a spring pressed stripper K maintains the corrugated fastener out of contact with the stationary knife K during the advance of the strip in the direction of its length into the guides G However, I do not wish to be limited in the carrying out of my method to this or other particular features of the apparatus or procedure as herein described, nor for use of my method for the forming of the penetrating end of the fastener, it being obvious that substituting a form such as plain edged, scalloped, castellated, serrated, or modifications thereof, for the toothed fastener as described, is not a departure from my method.

I claim:

1. The method of producing metallic fasteners comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge.

comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing without loss of metal, a swage-beveled severed strip having a beveled swage-hardened penetrating edge.

3. The method of producing metallic fasteners comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing without loss of metal a swage-beveled severed strip and subsequently bending and rebending the swage-severed strip to impart corrugations.

4. The method of producing metallic fastenerscomprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge and subsequently bending and rebending the swagesevered strip to impart corrugations.

5. The method of producing metallic fasteners comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge and subsequently bending and rebending the swagesevered strip to impart divergent corrugations.

6. The method of producing metallic fasteners comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge and subsequently bending and rebending the swagesevered strip to impart parallel corrugations.

'7. The method of producing metallic fasteners comprising simultaneously swage-beveling and swage-severing a metallic ribbon thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge, subsequently bending and rebending the swagesevered strip to form corrugations and thereafter cutting the corrugated strip into desired lengths.

8. The method of producing serrated metallic fasteners comprising simultaneously swagebeveling and sWage-severing metallic ribbon thereby producing a swage-beveled swage-severed serrated strip having a beveled swagehardened penetrating edge.

9. The method of producing serrated metallic fasteners comprising simultaneously swagebeveling and swage-severing metallic ribbon thereby producing without loss of metal a swagebeveled swage-severed serrated strip having a beveled swage-hardened penetrating edge.

10. In the art of making toothed corrugated fasteners from a metallic ribbon, the improvement which comprises forming by a single swage-severing operation two strips each strip having its swage-severed edge serrated and beveled, and thereafter bending and rebending the severed strips to impart corrugations there- 11. In the art of making toothed corrugated fasteners from a metallic ribbon, the improvement which comprises forming by a succession of swage-severing operations two strips each strip having its swage-severed edge serrated and beveled, and thereafter bending and rebending the severed strips to impart corrugations thereto.

12. The method of producing a metallic fastener comprising maintaining swage-beveling and swage-severing elements short of contact by means of contacting lands while swagebeveling and swage-severing their reverse formations i-ntometallic ribbon, thereby producing a swage-beveled severed strip having a beveled swage-hardened penetrating edge.

13. The method of producing serrated metallic fasteners comprising swage-beveling and swagesevering a metallic ribbon thereby producing a swage-beveled swage-severed serrated strip having a beveled swage-hardened penetrating edge and thereafter corrugating said serrated strip.

14. The method of producing serrated metallic fasteners comprising swage-beveling and swagesevering a metallic ribbon thereby producing without loss of metal a swage-beveled swage-severed serrated strip having a beveled swage-hardened.

penetrating edge, and thereafter corrugating said serrated strip.

15. The method of producing serrated metallic fasteners which comprises swage-beveling and swage-severing a metallic ribbon thereby producing. swage-beveled swage-severed serrated strips having a beveled sWage-hardened penetrating edge, thereafter corrugating said strips and subsequently severing a suitable length'from each strip.

16. The method of producing serrated metallic fasteners which comprises swage-beveling and swagesevering a metallic ribbon thereby producing Without loss of metalswage-beveled swagesevered serrated strips having a beveled swageihardened penterating edge, thereafter corrugating said serrated strips and subsequently severing a suitable length from each strip.

17. In the art of producing corrugated fasteners from fiat metallic ribbon indefinite as to length, the improvement which comprises swagebeveling and swage-slitting a flat metallic ribbon into sharpened beveled-edged strips without loss of metal, then corrugating the strip subsequently severing a suitable length from the corrugated strip thereby producing a finished. fastener.

18. The method of producing serrated fasteners from metallic ribbon indefinite as to length, which comprises swage-beveling and sWage-severing a metallic ribbon by a step by step movement in the direction of its length thereby producing a hardened swage-beveled swage-serrated penetrating edge on said strip, subsequently bending and rebending the strips to form corrugations and thereafter severing a suitable length from each strip.

19'. The method of producing fasteners from metallic ribbon which comprises swage-beveling and swage-severing a metallic ribbon by a step by step movement in the direction of its length thereby producing hardened swage-beveled penetrating edged strips, subsequently bending and rebending said strips forming corrugations and thereafter severing said strip transversely of the penetrating edge.

20. The method of producing metallic fasteners comprising simultaneously opposingly swagebeveling and swage-severing a metallic ribbon into strips having a beveled swage-hardened continuous cutting edge, then corrugating the strip transversely of the swage-beveled hardened edge forming a continuous undulating hardened cutting edge of greater hardness than the unswaged metal of the strip, and subsequently severing a suitable length from the strip.

21. In the art of making corrugated fasteners from a metallic ribbon the improvement which comprises advancing a ribbon indefinite as to length in the direction of its length into swaging relation with'respect to swage-b'eveling and swagesevering elements thereby swage-beveling and swage-severing the ribbon into two beveled edged strips, then: subsequently bending and rebending the severed strips transversely of the penetrating end, thereby producing a succession of corrugations, then severing a suitable length of strip from the corrugated strip thereby forming a finished cut-to-length fastener. 7

2-2. In the art of making toothed corrugated fasteners from a metallic ribbon the improvement which comprises the steps of advancing a ribbon indefinite as to length-in the direction of its length into swaging relation with respect to swage-beveling and swage-severing elements thereby swagebeveling and swage-severing the ribbon into two beveled edged strips, then passing said strips between corrugating rolls thereby corrugating the metal of said strips transversely of the penetrating. edge, then severing a suitable length of .strip from said corrugated strip thereby producing a cut-to-length finished fastener.

23.. In the art. of making toothed corrugated fasteners from a metallic ribbon the improvement which comprises advancing a ribbon indefinite asto. length in the direction of its length into swaging relation with respect to swage-beveling and swage-severing rolls thereby swage-beveling and swage-severing the ribbon into two swagebeveled edged strips, then corrugating said strips transversely of the penetrating edge, then guiding one of said corrugated strips exit the machine and the other of said corrugated strips into cutting relation With strip severing knives for severing desired lengths from the strip.

24. The method of producing toothed fasteners, which comprises employing a ribbon indefinite as to length, guiding the ribbon into swaging relation with co-acting rotating swaging rolls, swage-beveling and longitudinally severing the ribbon into strips having a beveled swage-hard-' ened. penetrating end on one edge of each strip, guiding the ribbon into operative relation with flattening rolls and thereafter guiding the ribbon into operative relation with corrugating rolls for corrugating the strips transversely of the penetrating end.

25,111 the art of making saw-toothed corrugated fasteners from fiat metal strip or ribbon,

the improvement which comprises producing two simultaneously severed beveled strips of sawtoothed fastener stock from one strip of metal, Without the removal of metal in the making thereof, by a combined swaging, beveling and slitting process and subsequently bending and rebending the severed strips to impart corrugations thereto.

26. The improvement in the art of making sawtooth type of corrugated fasteners from metal strip which comprises opposingly simultaneously swaging the strip intermediate the side edges thereof thereby producing reversed bevels upon the surface of the strip, the intersection of the planes of the bevels forming a continuous knifelike cutting edge, V-shaped when viewed in end section, on each of the simultaneously beveled separated opposingly swaged strips and producing well defined saw teeth on the penetrating edge of each strip, and subsequently bending the sharpened flat metal strip to impart corrugations thereto.

27. The improvementin the art of making saw-tooth type of corrugated fasteners from metal strip which comprises opposingly simultaneously swaging the strip intermediate the 75 edges thereof thereby producing reversed bevels upon the surface of the strip, the intersection of the planes of the bevels forming a continuous knife-like cutting edge, V-shaped when viewed in end section, on each of the simultaneously beveled separated opposingly swaged strips and producing well defined saw-teeth on the penetrating edge of each strip, and subsequently bending the sharpened flat metal strip to impart corrugations thereto and to position the points of the teeth in random staggered arrangement with respect to the medial line of the fastener.

28. The improvement in the art of making saw-tooth type of corrugated fasteners from metal strip which comprises opposingly simultaneously swaging the strip intermediate the side edges thereof thereby producing reversed bevels upon the surface of the strip, the intersection of the planes of the bevels forming a continuous knife-like cutting edge, V-shaped when viewed in end section, on each of the simultaneously beveled separated opposingly swaged strips and producing well defined saw-teeth on the penetrating edge of each strip, and subsequently bending the sharpened flat metal strip to impart corrugations thereto.

29. The improvement in the art of making saw-tooth type of corrugated fasteners from metal strip which comprises opposingly simultaneously swaging the strip intermediate the side edges thereof thereby producing reversed bevels upon the surface of the strip, the intersection of the planes of the bevels forming a continuous knife-like cutting edge, V-shaped when viewed in end section, on each of the simultaneously beveled separated opposingly swaged strips and producing well defined saw-teeth on the penetrating edge of each strip, and subsequently bending the sharpened flat metal strip to impart corrugations thereto and toposition the points of the teeth in the plane of the medial line of the corrugated metal.

30. The method of making metal fasteners which comprises guiding a ribbon indefinite as to length into swaging and slitting relation with co-acting swage-beveling rolls, advancing the ribbon thru the rolls at the same rate of travel as the rate of travel of the periphery of the rolls, thereby producing a plurality of sharp edged strips swage-beveled at an angle oblique to the plane of the fastener.

31. The method of making metal fasteners which comprises guiding a ribbon indefinite as to length into swaging and slitting relation with co-acting toothed swage-beveling rolls, advancing the ribbon thru the rolls at the same rate of travel as the rate of travel of the periphery of the rolls, thereby producing a plurality of toothed edged strips swage-beveled at an angle oblique to the plane of the fastener.

32. The method of making metal fasteners which comprises guiding a ribbon indefinite as to length into swaging and slitting relation with a series of paired co-acting toothed sWage-beveling rolls, advancing the ribbon thru the series of paired rolls at the same rate of travel as the rate of travel of the periphery of the rolls thereby producing a plurality of toothed strips beveled and sharpened on the penetrating edge.

33. The method of making metal fasteners which comprises guiding and advancing a ribbon in a definite path into swaging, beveling and slitting relation with opposed co-acting swaging rolls, maintaining the swaging surface of one of said swaging rolls short of contact with the swaging surface of its opposed roll.

34. The method of producing toothed fasteners, which comprises employing a ribbon indefinite as to length, guiding the ribbon into swaging relation with co-acting reciprocating swaging dies for sWage-beveling and longitudinally severing the ribbon into strips.

JOHN SHERMAN MCCHESNEY. 

